21030170 has 16 divisors (see below), whose sum is σ = 43262208. Its totient is φ = 7210320.

The previous prime is 21030127. The next prime is 21030181. The reversal of 21030170 is 7103012.

It is a Harshad number since it is a multiple of its sum of digits (14).

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 150146 + ... + 150285.

It is an arithmetic number, because the mean of its divisors is an integer number (2703888).

Almost surely, 2^21030170 is an apocalyptic number.

21030170 is an abundant number, since it is smaller than the sum of its proper divisors (22232038).

21030170 is a wasteful number, since it uses less digits than its factorization.

21030170 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 300445.

The product of its (nonzero) digits is 42, while the sum is 14.

The square root of 21030170 is about 4585.8663303677. The cubic root of 21030170 is about 276.0244762302.

Adding to 21030170 its reverse (7103012), we get a palindrome (28133182).

The spelling of 21030170 in words is "twenty-one million, thirty thousand, one hundred seventy".